Windows 8.1, formerly codenamed Blue: this is where Microsoft tries to win over those of you who've looked at Windows 8 and said, "not gonna happen". The changes in 8.1 are subtle but effective, especially if you want a little more Windows 7 in your Windows 8. Microsoft just made Windows 8.1 Preview available as a free download, and the release version will be out later this year (we're guessing by the end of October, to match Windows 8's October 26, 2012 release date). Windows 8.1 will be a free update via the Microsoft Store for all Windows 8 PCs.

You can download the 2.44 gig Preview via the Windows Store, but you'll need to download a helper app from Microsoft's website first. Alternatively you can download an ISO disk image file. But if you go with the ISO, you'll have to restore your Windows 8 PC back to stock Windows 8 before upgrading to the release version of 8.1. You probably won't want to do that with a machine you depend on. If you go with the Store route, you'll have to re-install your programs when 8.1 final is available (even your desktop programs, not just Metro apps). Don't want to go through all the hassle? Let us do it for you, and watch our Windows 8.1 walkthrough instead!

For our video walkthrough and review, we use the new Lenovo ThinkPad Helix, a convertible Windows 8 tablet and laptop in one. It has a full HD display and a Core i5 CPU.

2) Metro home screen has new customization features and more tile sizes.

3) The on-screen keyboard has long-press number keys on the top row, much like many smartphone and Android tablet keyboards. No more having to switch to the numeric on-screen keyboard.

4) Windows Store has a new look with bigger pictures, more info and suggestions.

5) The Start Menu icon is back. By default it toggles between Metro and desktop UI. Right click offers all sorts of useful commands, just as before and is equivalent to hitting the Windows + x keys on the keyboard.

You can change Start Menu button to show all programs, making it functionally more like the Windows 7 Start menu. Changing the Start Menu also reassigns the home button on a tablet and what the Windows key on hardware keyboard.

6) You can tell Windows 8.1 to boot to the Desktop rather than Metro UI.

7) You can use your own wallpaper or the desktop wallpaper as your Metro background. That makes for a much less jarring experience, and the Metro UI seems more like a program quick launcher instead of a separate OS.

Both Start Menu settings and Boot to Desktop are sorta hidden: in the desktop UI, right-click on the task bar and choose Properties. The new Navigation tab houses these settings.

8) Pulling down on the sleep screen opens the camera app. The lock screen can act as a photo frame, pulling images from the last year from local and SkyDrive galleries.

9) WiFi direct is now supported for things like printers and MiraCast video streaming direct to a TV.

10) IE 11 has speed and touch improvements.

11) Side by side app views in Metro improved. How many windows you can have tiled depends on display resolution. The new default is a 50-50 split and you can resize the panes.

12) Search is broadened, as Microsoft moves toward universal search.

13) Metro's Control Panel (Charms menu) has more settings now, so you don't have to resort to the desktop's control panel as often.

14) Now Metro apps get their own listing and removal tool.

15) The Computer icon on the desktop is now labeled "This Computer" and your user folders are listed at the top, so you don't need the User's Files shortcut on the desktop anymore.

16) Metro media players have an improved UI that makes it easier to browse to folders other than Videos and Music folders.

17) Display scaling is now handled by a slider rather than radio buttons with percentage selections. You can still resort to the percentage selector if you wish, but this will scale all displays the same, unlike the new sliding scale control.